1. Technical Field
An aspect of the present invention relates to an image reading apparatus having an edge detecting system, which is capable of detecting an edge of a sheet being conveyed in a sheet conveyer path.
2. Related Art
An image reading apparatus, in which a plurality of stacked original sheets are separated one-by-one and conveyed sequentially along a predetermined sheet conveyer path, is known. Whilst the original sheets are conveyed, original images appearing on the original sheets are sequentially read by an image reader.
In such an image reading apparatus, for example, the stacked original sheets may be separated by a feeder member and a separator member to be fed one-by-one along the sheet conveyer path toward a downstream side, in which an edge sensor detects a front edge of the original sheet being conveyed. Upon detection of the front edge of the original sheet, the image reading apparatus may control an image reader to read the original image on the original sheet.
For another example, an image reading apparatus with a roller, which contains a one-round clutch to separate and convey the stacked original sheets one-by-one, is known. The roller may include a cylindrical contact piece, which is to be in contact with the original sheet and is rotatable, and a drive shaft, which is rotated by a drive source. The drive shaft may penetrate the contact piece along an axial direction and allow the contact piece to idle for a predetermined, amount with respect to the rotation of the drive shaft. Therefore, depending on a position of the contact piece with respect to the drive shaft, the contact piece may be rotated along with the drive shaft or may be rotated regardless of the rotation of the drive shaft. In particular, the roller may separate and convey the original sheets when the contact piece is rotatable along with the drive shaft.